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<head>
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          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
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    <title>Document</title>
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    <style>
        i {
            font-weight: bold;
            color: red;
            margin-right: 8px;
        }

        ul {
            width: 100vw;
        }
        .input-group{
            margin-bottom: 10px;
        }
    </style>
</head>
<body>
<div class="input-group">
    <span class="input-group-addon" id="basic-addon1">开始数量: </span>
    <input type="text" class="form-control" placeholder="Username" aria-describedby="basic-addon1" value="1" id="start">
</div>

<div class="input-group">
    <span class="input-group-addon" id="basic-addon1">结束数量:  </span>
    <input type="text" class="form-control" placeholder="Username" aria-describedby="basic-addon1" value="1" id="end">
</div>
<p style="display: flex;justify-content: center">
    <button onclick="count()" class="btn btn-default">开始</button>
</p>

<ul class="list-group">
    <li class="list-group-item">
        <i>1</i>只青蛙,<i>1</i>张嘴,<i>2</i>只眼睛,<i>4</i>条腿
    </li>
</ul>
<script>
    const ul = document.getElementsByTagName('ul')[0]

    function count() {
        let html = ''
        let start = Number(document.getElementById('start').value)
        let end = Number(document.getElementById('end').value)
        for (let i = start; i <= end; i++) {
            html += `<li class="list-group-item">
            <i >${i}</i>只青蛙,<i>${i}</i>张嘴,<i>${i * 2}</i>只眼睛,<i>${i * 4}</i>条腿
        </li>`
            ul.innerHTML = html
        }
    }
</script>
</body>
</html>